Strain-rate Dependent Tensile Failure Behavior of 7075 Aluminum Alloy Sheet at Elevated Temperatures

The Strain-rate dependent tensile failure behavior of 7xxx series aluminum alloy sheet was investigated at elevated temperatures. In this study, a 7075 aluminum alloy sheet of thickness 1.27 mm was used. Hot tensile tests were performed for four strain-rates of 0.0001 s(-1), 0.001 s(-1), 0.01 s(-1) and 0.1 s(-1) at two temperatures of 400 degrees C and 470 degrees C. The deformation behaviors on the corresponding stress-strain curve was divided into five stages and total elongation and damage slope were measured. Local failure strains were obtained by measurements of the shape of the fractured specimen using a 3D scanner. As the strain rates increased, the total elongation and local failure strains increased for both 400 degrees C and 470 degrees C. Total elongation at 470 degrees C is slightly larger than that at 400 degrees C, while local fracture strains at 400 degrees C are significantly larger than those at 470 degrees C.